Bioactive conjugates for oligonucleotide delivery

Abstract

Provided herein are self-delivering oligonucleotides that are characterized by efficient RISC entry, minimum immune response and off-target effects, efficient cellular uptake without formulation, and efficient and specific tissue distribution.

The invention claimed is: 
     
       1. A method for selectively delivering a compound to the placenta of a patient, comprising administering said compound to the patient, wherein the compound has a formula (I): 
       
         
           
           
               
               
           
         
         wherein:
 O is a double-stranded nucleic acid comprising a first oligonucleotide and a second oligonucleotide, wherein:
 (1) the first oligonucleotide comprises at least 16 contiguous nucleotides, a 5′ end, a 3′ end and has complementarity to a target; 
 (2) the second oligonucleotide comprises at least 15 contiguous nucleotides, a 5′ end, a 3′ end, and has homology with a target; and 
 (3) a portion of the first oligonucleotide is complementary to a portion of the second oligonucleotide; 
 
 L is a trivalent linker; 
 X c  is a hydrophobic moiety; and 
 Z c  is a phosphodiester or phosphodiester derivative, or is absent, 
 wherein X c  comprises docosanoic acid (DCA) and Z c  is 
 
       
       
         
           
           
               
               
           
         
         wherein X is O, S or BH 3 . 
       
     
     
       2. A method for treating a disease or disorder of the placenta in a patient in need of such treatment, comprising administering to the patient a small interfering RNA (siRNA) of formula (I): 
       
         
           
           
               
               
           
         
         wherein:
 O is a double-stranded nucleic acid comprising a first oligonucleotide and a second oligonucleotide, wherein:
 (1) the first oligonucleotide comprises at least 16 contiguous nucleotides, a 5′ end, a 3′ end and has complementarity to a target; 
 (2) the second oligonucleotide comprises at least 15 contiguous nucleotides, a 5′ end, a 3′ end, and has homology with a target; and 
 (3) a portion of the first oligonucleotide is complementary to a portion of the second oligonucleotide; 
 
 L is a trivalent linker; 
 X c  is a hydrophobic moiety; and 
 Z c  is 
 
       
       
         
           
           
               
               
           
         
         wherein X is O, S or BH 3 ,
 wherein X c  comprises docosanoic acid (DCA), and 
 wherein the disease or disorder is selected from the group consisting of: a disorder associated with the expression of soluble Flt1 (sFlt1) protein, PE (preeclampsia), postpartum PE, eclampsia, and HELLP syndrome. 
 
       
     
     
       3. The method of  claim 1 , wherein L comprises an ethylene glycol chain, an alkyl chain, a peptide, RNA, DNA, a phosphodiester, a phosphorothioate, a phosphoramidate, an amide, a carbamate, or a combination thereof; and wherein L is attached to O via the second oligonucleotide. 
     
     
       4. The method of  claim 1 , wherein O comprises one or more chemically-modified nucleotides. 
     
     
       5. The method of  claim 1 , wherein the nucleotides at positions 2 and 14 from the 5′ end of the second oligonucleotide are 2′-methoxy-ribonucleotides. 
     
     
       6. The method of  claim 1 , wherein:
 the nucleotides at positions 1 and 2 from the 3′ end of the second oligonucleotide are connected to adjacent nucleotides via phosphorothioate linkages; and/or 
 the nucleotides at positions 1 and 2 from the 5′ end of the second oligonucleotide are connected to adjacent nucleotides via phosphorothioate linkages. 
 
     
     
       7. The method of  claim 1 , wherein the first oligonucleotide comprises a moiety X at the 5′ end, wherein X is selected from the group consisting of 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
       8. The method of  claim 7 , wherein:
 X is X3; and 
 L is 
 
       
         
           
           
               
               
           
         
       
     
     
       9. The method of  claim 1 , wherein the first oligonucleotide has 3-7 more nucleotides than the second oligonucleotide. 
     
     
       10. The method of  claim 1 , wherein:
 the first oligonucleotide has perfect complementarity to the target; 
 the second oligonucleotide has complete homology with the target; and/or 
 the target is mammalian or viral mRNA, wherein the target is optionally an intronic region of said mRNA. 
 
     
     
       11. The method of  claim 2 , wherein the siRNA targets a soluble fms-like tyrosine kinase-1 (sFlt-1) mRNA.